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Bicentennial gold 88 endowment: The university of Ballarat international geological excursion to New Zealand, 2006

- Carey, Stephen

  • Authors: Carey, Stephen
  • Date: 2007
  • Type: Text , Journal article
  • Relation: AusIMM Bulletin Vol. , no. 6 (2007), p. 81-82
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  • Description: The University of Ballarat organizes international excursion for its undergraduate geology students to provide them an opportunity to learn and gain international experiences of geology. The university previously organized an excursion of New Zealand in November-December 2006 to provide students knowledge about plate boundary and gold mineralization. The excursion was sponsored by Oxiana Limited, the Bicentennial Gold 88 Endowment, Newmont Australia Limited, and Castlemaine Goldfields Ltd. The excursion was planned for 17 days and visit to the Taupo Volcanic Zone, Kaikoura, The Waipara, Mt Cook and the Tasman Glacier, Macraes gold mine, Otago's silcretes, Queenstowm, and Milford Sound. More information about 2006-excursion can be found on the website at http://www.ausimm.com.au/main/education/award-bice-gold-php.

Grab sampling for underground gold mine grade control

- Dominy, Simon

  • Authors: Dominy, Simon
  • Date: 2010
  • Type: Text , Journal article
  • Relation: Journal of The South African Institute of Mining and Metallurgy Vol. 110, no. 6 (2010), p. 277-287
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  • Description: Geologists in some underground gold mines collect grab samples from broken ore piles or trucks as a method of grade control. It is often known as muck sampling. Generally, the goal of grab sampling is to try and reconcile the mined grade at the ore source to the predicted grade and/or predict the mill feed grade. The mass of the sample collected is limited by health and safety issues, as well as by the capacity of the laboratory to process the samples within a given time frame. In general terms, grab sampling is known to be problematic because samplers tend to oversample the fines, and/or pick out high-grade fragments; surface sampling of piles does not test material within the pile; muck piles in development drives/faces are likely to be zoned due to the blasting sequence; high or lowgrade material may preferentially segregate in the pile during mucking; the five per cent mass reject size of the material in muck piles is very large from underground blasting; some correlation usually exists whereby the larger fragments are enriched or depleted in the critical component of value; and the average error made in estimating the true stockpile grade is likely to be high. The method is prone to chronic fundamental sampling, grouping and segregation, delimitation, and extraction errors. Substantial warnings must be given about the use of grab sampling for grade control in gold mines. The method may appear to work sometimes, which can be attributed to a fine gold particle sizing and more disseminated distribution. As with all sampling methods, its appropriateness must be determined by ore characterization and heterogeneity testing to ensure the method suits the ore type. © The Southern African Institute of Mining and Metallurgy, 2010.

Application of thermal fragmentation in Australian hard rock underground narrow-vein mining

- Drake, Bradley, Koroznikova, Larissa, Tuck, Michael, Durkin, Steve

  • Authors: Drake, Bradley , Koroznikova, Larissa , Tuck, Michael , Durkin, Steve
  • Date: 2020
  • Type: Text , Journal article
  • Relation: Mining, Metallurgy and Exploration Vol. 37, no. 1 (2020), p. 219-229
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  • Description: This paper presents the results from the investigation of the application of thermal fragmentation in Australian hard rock underground narrow-vein mining. Two geologically similar samples from an underground narrow-vein hard rock gold mine were collected to obtain a measure of the technology’s ability to recover ore by the creation of large thermal openings to assess the applicability of the thermal method. Particle size distribution showed a higher generation of fine product, − 2 mm, by thermal fragmentation compared with selective blasting by 31%. The Bond work index for thermal ore (12.62 kWh/t) is half to that of the blasted ore value (25.32 kWh/t). The average grindability obtained for the thermal ore sample was greater than the blasted sample by a factor of 2.44, a higher value indicating a decrease in the energy required to grind. The thermal fragmentation method generates product with higher dissolution of gold in cyanide, by 14% for the − 9.5 + 2 mm size fraction samples. Additionally, the thermal fragmentation results in higher production of − 9.5 + 2 mm material by 15 % compared with selective blasting. © 2019, Society for Mining, Metallurgy & Exploration Inc.
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